Clinical performance of resin-bonded bridges: a 5-year prospective study. I. Design of the study and influence of experimental variables.

A total of 203 resin-bonded bridges were inserted under controlled clinical conditions and evaluated over a period of 5 years. The study included two experiments to test the influences of retainer type, cementation material and operator on the success rate of resin-bonded bridges. The overall survival at 5 years was 75%. Micromechanical retainers were better than macromechanical retainers. For inserting micromechanical retainers, the cementation materials Clearfil F and Panavia Ex were better than Conclude. An operator effect was not found in this study.